A sheep’s neck is spotted with blood, and lambs, newly delivered the day before, are missing. Ian Pease is worried and fears a dog attack.

“I have lost quite a few sheep over the years,” he tells me, “I will bring my trailer up later and bring the sheep back to the yard to check him.”

Ian is a ranger at Hatfield Forest and has worked here for 25 years. He is responsible for delivering and preparing firewood and herding the sheep, some from as far as the Hebrides, off the coast of Scotland.

I spent a day with three rangers, learning about their day-to-day tasks and how they are conserving the forest under pressure from the increasing number of visitors.

In the last 10 years the number of visitors to the forest has doubled, according to a National Trust planning advisor, which is putting considerable pressure on the forest, which extends over 1,000 acres.

In a letter to Uttlesford District Council planning department, Nina Crabbe, from the National Trust, said there are signs that sites of scientific interest and natural nature reserves in the forest are being damaged because of the rapid growth in visitor numbers.

Kimberley Goodall, 30, from Leeds, says permanent ranger jobs are like “gold dust” and most jobs only last months.

Responsible for the lake and its surroundings, Kimberley and her team of volunteers, including an 80-year-old keen litter picker, cut back brambles and scrubs around the lake, so that visitors can enjoy the same view the Houblon family had, after they bought the forest in 1729.

Winter is a “window of opportunity” for Kimberly to start coppicing; a woodland management technique which involves cutting back the growth.

She says she works in “quite a male-dominated field” and that her job is “not really geared towards women”.

Explaining, Kimberley says: “I would love to see more women rangers. We bring something different... I think we are just a bit more patient.”

Lead ranger Grant MacPherson, 37, who lives in Wimbish, had only been in the role for nine weeks when I spoke to him, and he previously worked at an estate in Kent owned by an Italian count.

I asked Grant about the damage being done to the forest because of the heavy footfall, and what visitors should do as we wandered through the paths.

He said: “Of course we want people to come and walk their dogs but maybe it’s finding that happy balance of the forest being used and not abused so its there for future generations.”

He added: “There’s so much development happening (in the area), there’s not really many other places to go and walk dogs.”

Ian, who lives in the grounds of the forest and plays the squeeze box in his free time, told me: “What’s lovely about this place is the generations of people that come. I have seen people that came here as kids now bringing their kids. You see volunteers that leave and then come back with their kids.”

As we make our way to the sheep in Ian’s 4x4 with Selena, a sheepdog in training panting in the back, I am given a quick lesson in forest conservation.

No doubt when visiting the forest you will have noticed cows dotted around and munching on grass. You may not have realised it, but the cows are performing an important duty for the forest.

By eating the grass the cows are preventing the area turning into woodland. Likewise, the sheep are moved to a different area after five years and clear all the “rank stuff” so the cows can graze on the land later.

Ian shows me trees which are growing and surrounded by natural barriers, to prevent the deer eating the trees. Once the barriers rot, they become compost. Summing up the different parts of the forest, Ian, 46, says: “It’s a patchwork quilt of habitats that provide this really important eco-system.”

A father of two boys, he rounds the sheep up every day, to count them, check them over and train Selena.

He explains: “You try to round up the sheep alone, the sheep just look at you and go, ‘okay mate’. Trying to do it with humans is impossible. It’s a nice historical thing. Sheep have been kept here for centuries.”

As we trudge back to the car, I ask Ian whether he finds his job isolating.

He responds: “We are a team. We see each other during the day but a lot of my time is just me on my own doing the sheep but I don’t mind that. It’s a way of life.”